/* This is the header file that contains the parameters for 
   pion photoproduction. */

#ifndef t_piprod_parameters_nonrel_h
#define t_piprod_parameters_nonrel_h




#define PI_M 139.6
                          /* pion mass (in MeV) */
                          /* 139.6 */
#define PIO_M 135.0        
                          /* neutral pion mass (in MeV) */
                          /* 135.0 */
#define PIM_M 139.6       
                          /* pion mass (in MeV) used in resonant multipoles */
                          /* 139.6 */ 
                          /* 138. averaged mass when working 
                             with neutral pions */
                          
#define NU_M 939.         /* nucleon mass in MeV */
#define DEL_M 1236.
                          /* delta mass in MeV */
                          /* 1236. non-relativistic,nonunitarized background */
                          
#define OMEGA_M 782.      
                          /* omega meson mass in MeV */
#define RHO_M 770.      
                          /* rho meson mass in MeV */

#define ELEC 0.302862     
                          /* electric charge e */
			  /* with pow(e, 2) / (4 * PI) = 1 / 137 */
#define CONV 1.           /* CONV = 1. turns ON the convection part in the 
                                       nucleon born diagrams,
                             CONV = 0. turns OFF the convection part in the 
                                       nucleon born diagrams */
#define ANTI_NUCL 1.      /* ANTI_NUCL = 1. turns ON the antinucleon 
                                            contribution,
                             ANTI_NUCL = 0. turns OFF the antinucleon 
                                         contribution */

#define P_MAGN 2.79       
                          /* magnetic moment of proton */
#define N_MAGN (- 1.91)   
                          /* magnetic moment of neutron */
#define F_PINN 1.00265  
                          /* coupling constant f_pinn */
			  /* with pow(f_pinn, 2) / (4 * PI) = 0.08 */
                          /* 1.00265 */ /* 0.97 */     
#define G_OMEGANN 15.85    
                          /* coupling constant g_omegann */
			  /* with pow(g_omegann, 2) / (4 * PI) = 24.9 */
                          /* 17.7 */ /*  15.85 */  
#define G_OMPIGA 0.314    
                          /* coupling constant g_omega-pi-gamma */
                          /* 0.314 */ 
#define G_RHONN 2.63      
                          /* vector coupling constant g_rhonn */
			  /* with pow(g_omegann, 2) / (4 * PI) = 0.55 */
                          /* 2.63 */ /* 3.19 */  
#define KAPPA_RHO 3.71     
                          /* tensor to vector coupling constant for rho  */
                          /* 3.71 */ /* 6.1 */ 
#define G_RHONPIGA 0.131
                          /* coupling constant g_rho-pi-gamma */
                          /* 0.131 */
#define G_RHOCPIGA 0.103
                          /* coupling constant g_rho-pi-gamma */
                          /* 0.103 */


#define LAMBDA_PINN 1200.  
                           /* 1200. */
                           /* pion-nucleon-nucleon vertex cut-off */
#define LAMBDA_OMEGANN 1500. 
                           /* 1500. */  
                           /* omega-nucleon-nucleon vertex cut-off */
#define LAMBDA_PINDEL 13000.  /* 250 */
                           /* cut-off at the crossed pi_nucleon-delta vertex */


#define F_PINDEL 2.127
                           

#define F_GANDEL 0.117     
                           /* M1 coupling constant f_gandelta */
#define F_GANDEL_E2 0.0009     
                           /* E2 coupling constant f_gandelta */
                           /* 0.0009 */
#define G_GANDEL_M 2.75
                           /* magnetic coupling constant g_gandelta */
                           /* 3.10 nonrelativistic, nonunitarized background */
                           /* 2.75 relativistic, unitarized background */
                                       

#endif